4 mm flavor lines run from the outlet valves to the glass

Smaller flavor opening
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4 mm socket
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Stem reducersR25 return
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Stem reducers and metric rear bulkheads carry continuous black tubing through a smaller dispense opening. The internal returns keep R25 bends.
Each flavor path uses an ARD4M4-E in its outlet valve, black 4 mm OD / 2.5 mm ID LLDPE, an ABU44M-E rear bulkhead and one continuous black tube to the faucet face. Both faucet finishes use black flavor tubing.
The organizer, FLAVOR collars, rear chips, wall holes and tube retention match the smaller stock. Flavor A crosses the front coils and uses a 4 mm cap on its lid bearing. Flavor B uses a west-wall tie saddle clear of the water feed. Both internal paths hold R25 or larger.
The 27 mm gooseneck retains the joint walls and the soda/cable clearance. The drink opening follows the smaller flavor pair without a central divider. The purchased mounting plate and its mating passage keep their dimensions.
The unit 1 shopping list credits the reducers and bulkheads delivered October 9. One 25 ft length supplies the black 4 mm tubing for this machine. The geometry and qualification scope distinguishes CAD clearance from physical fit and installed-path dosing.
Derek: “I'd like to switch to 4mm OD tubing for the dispense lines.”